You can use C# from F#, of course, but then you can run into issues with nulls and things like that. There's a reason every programming language has their own i

You can use C# from F#, of course, but then you can run into issues with nulls and things like that. There's a reason every programming language has their own implementation of JSON/XML parsing, HTTP and things like that: offering an idiomatic API is important. Last time I use the VSCode F# plugin (around a year ago), the experience was strictly worse than rust-analyzer. The compiler errors are also not as good. I've never used Rider so I can't comment on that. You're right about the 20 years of production code for C#. NuGet lists 241418 packages compared to crates.io 61579 crates, and there's a good chance most of them are more mature than the Rust alternatives. However that's C#, not F#, and I doubt F# represents more than 10% of the packages. That's still better than doing it yourself if there's no package or writing bindings to C though. I still think F# and Scala are solid choices if you want a functional language today, but it's not the "garbage collected Rust" ideal I wish we had.